John Dominic Crossan
Crossan [Historical Jesus] (275) notes that this parable is one of several complexes that express a criticism of wealth. In this case the farmer has not done anything wrong:
He is simply rich and has the planning problems of such status. But riches do not save you from death's unexpected arrival.
The views of the Seminar can be represented as follows:
The commentary in [The Five Gospels] notes the Lukan context (Luke 12:13-34) in which several elements address questions concerning possessions:
13:13-15 Warning against greed
13:16-21 Parable of the rich farmer
12:22-32 Do not be anxious
12:33-34 Treasure in heaven
While some Fellows of the Seminar were influenced by the lack of distinctive traits to distinguish this saying from the typical moral instruction of the wisdom tradition, most noted the simpler version preserved in Thomas (without either the introductory or concluding remarks found in Luke 12:15 and 12:21 respectively). The commentary continues:
Further, this parable can be seen as making a metaphorical point similar to that of the other parables that portray an inappropriate response to the coming of God's imperial rule. Examples include the parables of the money in trust (Luke 19:12b // Matt 25:14-30); the unforgiving slave (Matt 18:23-34); the Pharisee and the toll collector (Luke 18:10-14); and the response of the elder brother in the parable of the prodigal son (Luke 15:11-32). This farmer, like the useless and unforgiving servants, the earnest Pharisee, and the elder brother, fails to respond appropristely to the situation.
Samuel T. Lachs
[Rabbinic Commentary on the New Testament] (291f)
Rabbinic teaching does not eschew the material things of life, but it does not make of them the ultimate goal of man's existence. Man possesses an insatiable appetite, hence the statement, "Man's nature is such that he is never satisfied." [B. Sanh. 29b] There are many admonitions about the evil of covetousness and avarice, e.g., "A Rich man is compared to a mouse lying on dinars." [Ibid. Cf. also Sira 2.1-11; Ps. 49.16-20; Job 31.24 ff]
Lüdemann [Jesus] (345f) comments:
The authenticity of this passage is sometimes defended by designating it an 'eschatological parable' (J. Jeremias). But it is certainly not that. It is the narrative by a wise man indicating that riches mean nothing in the face of death. As one who knew the traditions of Israel, especially as he had called the poor blessed (6.20), Jesus may have thought that. But each time the context is quite different. If 6.20 is authentic, then 12.16-20 must be inauthentic. Jesus had other concerns than the fate of individual rich men, all the more so as the case mentioned in the parable was not and is not the rule.